Apparatus for emptying centrifuges



Sept. 2, 1941. p VAN R|E| 2,254,985 APPARATUS FOR EMPTYING CENTRIFUGES I Filed Dec. 6, 1939 Jag/s.

Patented Sept. 2, 1941 APPARATUS FOR EMPTYING CENTRIFUGES Pieter van Riel, Delft, Netherlands, assignor to Machinefabriek Reineveld N. V., Delft, Netherlands, a company of the Netherlands Application December 6, 1939, Serial No. 307,901 In the Netherlands December 14, 1938 2 Claims.

This invention relates to horizontal centrifugal machines of the type wherein the drum is provided with a knife for removing solid substances deposited on the inner wall of the drum, without stopping the machine. Its object is to provide simple and reliable means for guiding said knife in its movement towards and away from said wall, in such a manner that the knife, during its scraping or peeling action, is held in the correct position notwithstanding the fact that it is then subjected to considerable strains.

In accordance with this invention, the knife holder is rigidly secured to a rod adapted for lengthwise movement at substantially right angles to the axis of the machine, and provided with a lateral arm whose free end is slidably mounted in a guideway arranged in parallel relation with said rod and adapted to prevent the latter from rotation about its own axis.

The rod is preferably mounted vertically, with its lower end projecting into a hydraulic cylinder, which functions as a shock absorber, but also forms the means for forcing the knife secured to the upper end of the rod upwards towards the inner wall of the drum,

Referring to the drawing, which by way of example illustrates one embodiment of the invention:

Fig. 1 is a front view of a horizontal centrifuge, and

Fig. 2 is a top plan view thereof.

3 is the stationary casing of the centrifuge, 3 is the drum and 3 is the shaft thereof. The front wall thereof is provided, near the top and near the bottom, with heavy eyes or braces l and 4 respectively, for guiding a vertical rod 5, the lower end of which forms a plunger projecting into an oil cylinder 6.

Rigidly clamped to rod 5, intermediate the eyes 4 and 4 is a split sleeve 1, which is integral with the holder 8 of a knife 8. Also integral with said sleeve is a horizontal, bifurcated arm 9, which extends to the outer edge portion of the front wall of easing 3 and in substantially parallel relation with said wall. The outer end of said arm 9 is rectilinearly movable on a guideway l secured, in parallel relation with the rod 5, on the front wall of the casing 3.

As shown in Fig. 2, said guideway is formed by one flange ll] of a channel-shaped member H), which flange is straddled by the bifurcated end portion of arm 9. The inner faces of the fork prongs are provided with antifriction blocks 9*, V

the outer one of which is adapted for adjustment by means of bolts S! so that any undue clearance can readily be taken up. In this manner, rod 5 is efilciently prevented from rotation under the influence of the forces acting on knife 8 during its scraping or peeling action.

If it is desired for a layer of solid substances deposited o the inner wall of the rotating drum to be removed, rod 5 with the knife 8 secured to the top end thereof has to be moved upwards, so that the knife enters said layer. To this end, oil or another suitable pressure medium is admitted to cylinder 6 near the bottom thereof, whereby the plunger formed by the lower end of rod 5 is forced upward, After removal of said layer, the inflow of oil into cylinder 6 is checked and the oil in the cylinder allowed to escape through a comparatively narrow outlet under the weight of the descending rod 5 with associate parts. Thus, the cylinder 6 acts as a shock absorberfor reducing the falling velocity of said rod.

What I claim is:

1. In a centrifugal machine, a stationary casing, a drum mounted on a substantially horizontal shaft for rotation within the casing, a rod adapted for lengthwise rectilinear sliding movement in a direction substantially at right angles to the drum shaft, braces on the casing on either side of the shaft for guiding the rod in its lengthwise movement, a knife holder rigidly attached to the rod intermediate said braces, a scraper knife carried by the holder, said knife extending into said drum and having its cutting edge disposed parallel and in close proximity to the inner surface thereof, an arm rigidly attached to the rod intermediate the braces and extending at substantially right angles to both the shaft and the rod, and a runway on the casing for guiding the free end portion of the arm in parallel relation with the rod so as to prevent rotation V of the rod about its own axis.

2. In a centrifugal machine, a stationary casing, a drum mounted on a substantially horizontal shaft for rotation within the casing, a rod adapted for lengthwise sliding movement in a direction substantially at right angles to the drum shaft and having an inclination of at least 45 relative to a horizontal plane, braces on the casing on either side of the shaft for guidingthe rod in its lengthwise movement, a knife holder rigidly attached to the rod intermediate said braces, a scraper knife carried by the holder, said knife extending into said drum and having its cutting edge disposed parallel and in close proximity to the inner surface thereof, an arm rigidly attached to the rod intermediate the braces and extending at substantially right angles to both the shaft and the rod, a runway on the casing for guiding the free end portion of the arm in parallel relation with the rod so as to prevent rotation of the rod about its own axis, and a fluid actuated piston connected to the rod for moving the latter.

PIETER VAN REL. 

